There are several factors which are critical to the commercial success of UV (ultraviolet light) and EB (electron beam) curable coatings and inks. As printing presses and coater equipment run at higher and higher speeds, reducing the hourly cost of production, there are increasing demands on the curing speed of inks and coatings. At the same time, there is considerable focus by converters on energy consumption, such that there is a trend toward lower mercury lamp energies, and in many cases, conversion to LED light sources. Both higher line speeds and lower intensity light sources place demands on the reactivity of the monomers and oligomers used in formulations for such applications.
Another important factor for packaging applications is the increasing use of film substrates in bags, pouches, and labels. These substrates are very thin, but as a result, any shrinkage that occurs in the coating and ink during the curing process can result in wrinkling or other distortion of the film. Furthermore, in some cases, there is adhesion loss of the ink or coating to the film. Since these films are often used to package foods or beverages, there are very strict limits on the migration of unreacted monomers from the ink or coating.